Sectional hot-water boiler.



No. 699,l36. Patent'ed May 6, I902.

' B. F. BEHRENDT.

SECTIONAL HOT WATER BOILER.

(Application filed. Jan. 4, 1901.)

(No Model.) 4 Sheets-Sheet I.

m: mums PETERS 00.. PHOTO-L1TNO., WASHINGTON. n. c.

4 Sheets-Sheet 2.

Patented May 6, I902.

B. F. BEHRENDT.

. SECTIUNAL HOT WATER BOILER.

(Application filed. Jan. 14, 1901 (No Model.)

N0. 699,!36. Patented May 6, I902.

B. F. BEHBENDT.

SECTIONAL HOT WATER BOILER.

(Application filed Jan. 01-) I (No Model.)

4 Shets-$heet 3.

THE NORRI5 PETERS CO. PHOTO LITNO WASHINGTON, D. C.

No. 699,86. Patented May 6, I902. B. F. BEHRENDT. SEGTIONAL HOT WATER BOILER.

(Application filed Jan. 14, 1901.)

(No Model.) 4 Sheets-Sheet 4.

THE Norms PETERS 00.. FHOTO-LITHEL, WASHINGTON. n. c.

UNITED STATES PATENT OFFICE.

BRUNO FELIX BEHRENDT, OF DRESDEN, GERMANY, ASSIGNOR TO PFLAUM & GERLACH, OF SCHNEBERG, NEAR BERLIN, GERMANY.

SECTIONAL HOT-WATER BOILER.

SPECIFICATION forming part of Letters Patent No. 699,136, dated May 6, 1902. Application filed January 14, 1901. Serial No. 43,144. (No model.)

To all whom, it may concern:

Beit known that LBRUNO FELIX BEHRENDT, engineer, a subject of the King of Prussia, Emperor of Germany, residing at 19 Grunaerstrasse, in the city of Dresden, Kingdom of Saxony, German Empire, have invented a certain new and useful Improvement in Sectional Hot-Water Boilers, of which the following is a specification.

IO The improvements consist in arrangements for obtaining as perfect a combustion and as complete a utilization of the fuel as possible by means of a secondary supply of heated air to the combustion-gases inseparate com paratively thin currents after said gases have passed from the furnace-space. For this purpose I form between the water-chambers of adjacent sections small channelsfor the secondary air-supply, the walls of which are heated by the combustion-gases or flames and open into the flues for the latter near to the furnace, so that the heated air mixes with the said gases or flames in thin jets.

On the drawings appended hereunto a sectional boiler provided with such channels for secondary air-supply is shown as an example of the manner in which the invention may be carried into efiect; but'I do not confine myself to the special construction of boiler shown, as such channels can obviously be arranged in many ways and applied to sectional boilers of various forms.

Figure 1 represents a vertical cross-section,

Fig. 2 a vertical longitudinal section, and

I 3 5 Fig. 3 a horizontal section, of the boiler; Fig.

3, a modification; Figs. 4, 4 4*, and 4", the

damper for regulating the air-supply in var'iouspositions.

The boiler consists of the separate elements 40 or sections a, forming hollow chambers of the section shown by Fig. 3, which when joined together form heating-fines 12 between them,

while their interior forms the water-chambers 0. These water-chambers are connected at the upper and lower ends by means of the ferrules d, expanded in the known manner,

so that the water supplied through the branch pipe 6 circulates through all the chambers.

The water-chambers c inclose, as shown by Figs. 1 and 2, the furnace i, the end sections being formed with water-jacketed end walls.

The furnace is separated by the grate g from the ash-pit hand forms in its upper part the storage-room for the fuel, which is introduced through the filling-chute 7o. I

The central hollow rib Z, Fig. 3, of each section a, however, does not continue all around the same like the lateral hollow ribs or flanges m, but stops short of the top of the section, as shown on Fig. 1, so that the combustion-gases 6o flow in the direction shown by the arrows from the furnace through openings m of the internal flange m to the top, then turn around the end of the rib Z and pass downward and escape into the chimney-flue n.

The ribsland lateral flanges m being filled with water cannot burn off, but increase the heating-surface considerably.

The use and arrangement of hollow lateral flanges m, filled with the water, for forming the boiler-fines, constitutes an important improvement in comparison with the sectional boilers hitherto made, in which instead thereof solid flanges or ribs are used. The latter transfer the heat of the combustion-gas directly to the fuel filling the space 2', so that the heat absorbed by them is lost for the purpose of heating the water and even acts forming channels for the admission of a secondary air-supply to the fines.

In the example of boiler shown on the drawings the central rib Z is made use of for 0 this purpose, semicircular recesses 0, Fig. 3, or rectangular recesses, Fig. 3, being formed in its face, so that when the boiler-sections a are joined there is formed between each section an air channel or passage communicat- 5 ing with the outer air below the ash-pit. This channel preferably does not extend to the top of the central rib, but opens, as shown by Fig. 1, shortly above the entrance m for the combustion-gases into the inner-one of the fiues 6, formed by the sections, so that the air flowing through the channels 0 mixes directly with the combustion gases or flame immediatelythcy have left the furnace. By these means a complete or an almost complete combustion is obtained, and consequently such a temperature of the flame as is not reached with any of the previously known hot-water boilers. This effect is produced not merely by the supply of additional air but by dividing this secondary air-supply into a large number of comparatively thin currents. This assures not onlya correct and intimate mixture of the air with the combustion-gases, but also a uniform heating of this fresh air, notwithstanding the short way during which it is in contact with heating-surface, so that on mixing with the combustiongases no reduction of the temperature occurs, causing smoke to be evolved; but all those components of the gases capable of further combustion are burned. These airchannels further form a very convenient means for regulating the heating elfect of the sectional boiler, for if the air-inlet to these passages is provided with one opening sliding upon the mouthpiece of the ash-pit, which is provided with two openings q and r on Fig. l, is set in the position shown by Fig. at, so that the upper opening of the supply of air under the grate is left quite open, while the lower opening 7* for admitting air to the channels 0 is quite closed. During normal working the slide sis shifted to the position shown by Fig. 4", so that both openings are partly open, and the required air can pass under the grate and the secondary air for the fines can flow through the channels 0 in such relative quantities as is required for perfect combustion. As the hot gases in working are in contact with a part of the internal walls and the whole of the external walls of the channels 0 and these channels have only a small area, the secondary air mingles at such a temperature with the combustion-gases that a high percentage of combustion results, and the water soon obtains the desired temperature. If the temperature rises above the admissible degree, the slide 8 is pushed into the position, Fig. 4, in which the admission of air below the grate is quite shut off, and the air-inlet to the channels 0, on the contrary, fully opened. The secondary air then flows in excess to the combustion-gases, has a cooling action upon the fines, and arrests the heating eifect.

The slide 3 may be shifted by hand or by means of a suitable mechanical apparatus.

The heating etfect of the boiler thus can not only be considerably increased by means of the air-supply channels 0, but also quickly moderated and quite stopped, which is not possible with the furnaces of hot-water boilers as hitherto made.

What I claim, and desire to secure by Letters Patent of the United States, is-

1. A sectional hot-water boiler provided with vertical heating-fines formed by the abutting water-chambers, secondary vertical air-supply channels also formed by the abutting water chambers which channels are partly or entirely heated by the combustiongases and com municate with the heating-fines in such a manner that fresh heated air is supplied to the fines in separate jets adjacent to the point where the gases leave the furnace, substantially as described.

2. A sectional hot-water boiler provided with vertical heating'flues and with channels for a secondary air-supply, such fines and channels being formed by the abutment of the sectional water-chambers, substantially as described.

3. A water-boiler com posedof abutting sections joined together at the central top and bottom portions to form a boiler, each of which sections is of such form in cross-section as with the abutting section on either side to leave between them on the inner side a vertical flue or passage for the products of combustion located within the boiler so formed, which vertical flue is in communication at the top with a like descending flue formed in like manner, a smaller flue in communication at its top end with the first flue adjacent to its lower end being formed in like manner between the other two flues for feeding heated air to the first-named flue, substan tially as shown and described.

In witness whereof I have hereunto set my hand in presence of two witnesses.

BRUNO FELIX BEI'IRENDT.

\Vitnesses:

WOLDEMAR HAUPT, HENRY HASPER. 

